(1) Field of the Invention
This invention relates to a process for the preparation of chlorinated olefins of the following general formula (I), ##STR3## wherein R is an alkyl, aralkyl or alkenyl group substituted or not substituted by a lower acyloxy, lower alkyloxy, alkenyloxy or benzyloxy group.
The chlorinated olefins produced by the method of this invention shown in the general formula (I) are utilized as intermediates for the synthesis of various terpenoids which are in use of perfumes, feed additives, medicines and the like. [See .circle.1 Japanese Patent Laid-open No. 59-106434, .circle.2 Japanese Patent Laid-open No. 60-136549, .circle.3 Japaneses Patent Laid-open No. 61-194047, .circle.4 Bull. Chem. Soc. Japan, 59, 3287 (1986).]
(2) Description of the Related Art
It has been reported that chlorinated olefins of general formula (I) can be prepared by the chlorination of the olefins shown as the general formula (II) with one of the following chlorinating agents, ##STR4## wherein, R is the same as defined in the general formula (I).
.circle.1 Diaryl diselenide and N-chlorosuccinimide [see J. Org. Chem., 44, 4204 (1979)].
.circle.2 Hypochlorous acid prepared by the reaction of calcium hypochlorite and dry ice [see Tetrahedron Lett., 21, 441 (1980)].
.circle.3 Hypochlorous acid or oxygen dichloride prepared by the electrolytic oxidation of chloride ion [see Tetrahedron Lett., 22, 2291 (1981)].
.circle.4 t-Butyl hypochlorite [see Chem. Lett., 141 (1982)].
.circle.5 Trichloroisocyanuric acid and its derivatives [see Japanese Patent Laid-open No. 58-52231].
.circle.6 Sulfuryl chloride [see Chem. Pharm. Bull., 32, 3952 (1984)].
.circle.7 Oxygen dichloride [see Chem. Lett., 877 (1984)].
The above mentioned conventional methods of preparing chlorinated olefins have the following problems.
Method .circle.1 : Both diaryl diselenide and N-chlorosuccinimide are expensive.
Method .circle.2 : Difficulty in work-up procedure because of low solubility of calcium carbonate in water.
Method .circle.3 : Not in general because of the need of electrolytic reaction apparatus.
Method .circle.4 : Unsuitable for the preparation in large quantity because of the unstability and expensiveness of t-butyl hypochlorite.
Method .circle.5 : Difficulty in work-up procedure because of low solubility of generated cyanuric acid in organic solvents.
Method .circle.6 : Necessity of keeping the very low temperature at the reaction is not suitable for a commercial scale production.
Method .circle.7 : Oxygen dichloride is very dangerous to handle in large quantity because of its explosiveness.
As mentioned above, the conventional methods of preparing chlorinated olefins are difficult to adopt in a commercial scale production because of the problems, such as (i) expensive reagents, (ii) difficulty in work-up procedure, (iii) unstable reagents which are dangerous to handle in large quantity, (iv) necessity of special reaction apparatus, (v) necessity of special reaction condition.
Accordingly, an object of this invention is to provide a process for preparing chlorinated olefins of general formula (I) in commercial scale dissolving the above mentioned problems.
Other objects, features and advantages of this invention will become apparent from the following description.